The first time I read My Sytem I deemed the term "system" to be somewhat exaggerated. The first time I read only the text, while ignoring the games mostly. The system looked like a bunch of quite inspiring ideas, hinched losely together.
Now, the second time however, I'm more thorough. And indeed I'm starting to see the contours of a System which I completely missed before.
Take for instance the following game between Nimzowitch and Tarrasch:
Black to move.
Nimzowitch writes about this position:
"The position we have here appears really harmless but is actually extremely dangerous. White is threathening to occupy the c-file and in addition he has a comfortable square for his king (e2) while it is hard to say as much for black. In positions like this, the defender must play with extreme care."
Most clubplayers I know would call this a fairly level position. Even Rybka agrees with this. So where does the danger stemms from? What Nimzowitsch shows here is that the danger lies in floundering around a bit in the belief that this position is equal. While Tarrasch is dabbling around, Nimzovitsch found a good move each time thanks to his System. His System inspired him where to look. The positon can only be kept level if black finds equally good moves as white. But since black doesn't use a System he wasn't able to find the right answer everytime. (I assume that Tarrasch used a system but not The Sytem:)
Nimzovitsch describes his ideas often quite poetic. The good thing about this is that it helps you to remember the points he is making. It is often witty and easy to read. Which is pretty rare for a chessbook. The downside of this is that it obscures matters and invites you to interpret his findings as "rules", dismissing us from thinking ourselves. The only way to come around this is to study the games in the book with extreme care and to read his comments very well en open minded.
As a result you can't get the information of Nimzovitsch from second hand. Since second hand writers miss out the tiny yet important little details. Which they tend to replace by their own inventions or mix up with their own ideas.
Dvoretsky said that a carefull study of My System lead him to masterlevel in no time. I belief him.